The GPS only model will work anywhere the iPhone it is paired with works.
You will need an iPhone 6s, SE (1 or 2), 7 or newer.
HOWEVER, the warranty is going to be U.S. based, so if you have warranty issue, you may have difficulties getting it repaired under warranty in India.
You should also check if there are regional restrictions
https://www.apple.com/watchos/feature-availability/
If this is actually a used Apple Watch, then make sure your friend follows the following instructions
https://support.apple.com/en-us/HT208855
If it is brand new, never been opened Apple Watch, then that is not an issue.